Answer:
s an example, the ground state configuration of the sodium atom is 1s22s22p63s1, as deduced from the Aufbau principle (see below). The first excited state is obtained by promoting a 3s electron to the 3p orbital, to obtain the 1s22s22p63p1 configuration, abbreviated as the 3p level.
Explanation:
A barometer is the answer
<h3>
Answer:</h3>
318.405 g
<h3>
Explanation:</h3>
We are given;
- Volume of K₃PO₄ solution to be prepared as 750.0 mL or 0.75 L
- Molarity of the solution to be prepared as 2.00 M
We are required to determine the mass of K₃PO₄ to be measured.
<h3>Step 1: Determine the number of moles of K₃PO₄</h3>
Molarity = Moles ÷ Volume
Rearranging the formula;
Number of moles = Molarity × Volume
Therefore;
Moles of K₃PO₄ = 2.00 M × 0.75 L
= 1.5 moles
<h3>Step 2: Determine the mass of K₃PO₄ to be measured</h3>
Mass = Number of moles × Molar mass
Molar mass of K₃PO₄ = 212.27 g/mol
Therefore;
Mass of K₃PO₄ = 1.5 moles × 212.27 g/mol
= 318.405 g
Therefore, the mass of K₃PO₄ that should be weighed is 318.405 g
Answer:
Kₐ = 9.9 × 10⁻³
Explanation:
HClO₂ + H₂O ⇌ H₃O⁺ + ClO₂⁻
0.080 × 1.43 = 0.1144
So, at equilibrium,
[H₃O⁺] = [ClO₂⁻] = 0.1144
[HClO₂] = 1.43 – 0.1144 = 1.316
Kₐ = {[H₃O⁺][ClO₂⁻]}/[HClO₂]; Substitute values
Kₐ = (0.1144 × 0.1144)/1.316 Do the operations
Kₐ = 9.9 × 10⁻³
Q=mc(deltaT)
Q is the amount of energy which you are looking for
M is the mass which you can find
C is the specific heat of water which is 4.18 J/gC
DeltaT is the change in temperature which you can find.
To find the mass, first you must know that the density of water is 1g/mL, meaning that 200 mL has a mass of 200 g. This means that to find the total mass (m in the equation) all you need to do is add the mass of water and NaOH.
200 g + 2.535 g=202.535 g.
To find deltaT you would need to take the final temperature minus the initial temperature.
27.8C-24.2C=3.6C
Then these values can be substituted into the equation:
q=(202.635g)(4.18J/gC)(3.6C)
Q=3049.25 J
Technically this should be rounded off to 1 significant figure (200 mL only had 1), but ignoring signficiant figure rules this should be correct. Also, sometimes other units like calories or kJ may be asked for, meaning that a conversion or alternate c value would be used.
